Printers that have an inkjet head for ejecting ink onto a conveyed medium (for example, a continuous paper S), and a vacuum platen (also referred to as a suction panel) having a platen surface on which the medium is placed, and numerous suction holes formed in the platen surface, are known from the literature.
JP-A-2010-264624 described a printer of this type, in which the suction holes are widened toward the platen surface to increase the suction area. JP-A-2010-264624 also describes evening the pressure distribution in the suction holes and improving manufacturability when forming the suction holes by making the suction holes funnel-shaped with the top of the suction holes widened toward the platen surface.
However, if a gap opens between the side edge of the medium and the suction holes in this configuration, this gap and the smallest part of the opening in the suction holes can easily communicate perpendicularly to the platen surface. As a result, sufficient suction is not applied to the medium, and the medium can easily lift away from the platen surface.
More specifically, if the shortest distance between the edge of the wide end of the suction hole along the platen surface and the edge of the smallest opening of the suction hole is value Y, and the size of the gap (formed between the side edge of the medium and the suction holes) is greater than or equal to shortest distance Y, the gap and the smallest opening can communicate in a straight line to the platen surface. As a result, suction from the vacuum platen pulls in air from the outside, and the suction applied to the medium decreases.